Abstract: Integral impeller five-axis double-row slotted plunge milling can efficiently complete the machining of the integral impeller runner with a minimum number of plunge milling processes.However, for the impeller runner with excessive blade tilting, there are a lot of residual materials after the integral impeller five-axis double-row slotted plunge milling.Due to the lack of a precise calculation model for expressing the residual material, it is difficult to plan the follow-up machining path for the residual materials, which affects the processing efficiency.Regarding this issue, a geometric modeling method of residual material is proposed based on integral impeller five-axis double-row slotted plunge milling.Based on the plunge milling processes parameters of integral impeller five-axis double-row slotted plunge milling, simplify the residual material step surface into an ideal surface composed of a ruled surface and a blade normal vector, obtaining the boundary curve of residual material geometric modeling based on the geometric relationship between the ideal surface and the subsequent tool vector path.Discretize the boundary curve with a certain number, construct a discrete element ruled surface, and form a residual material envelope model to complete the geometric modeling of the residual material.The accuracy of geometric modelling is analysed through simulation, and the results showed that the average error of the model in describing the geometric features of complex residual materials is around 8%.This can provide reference for the study of CAM algorithms for the removal of residual materials from impellers.

Key words: double row slotting, plunge milling, five-axis machining, geometric modeling, envelope model, material residual ridge